/*
 *   Copyright 1999-2018 dragonshard.net.
 *   Licensed under the Apache License, Version 2.0 (the "License");
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the License at
 *        http://www.apache.org/licenses/LICENSE-2.0
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */
package net.dragonshard.dsf.core.toolkit;

import static java.util.stream.Collectors.toList;

import java.util.Collections;
import java.util.List;
import java.util.Map;
import net.sf.cglib.beans.BeanMap;

/**
 * Bean 转换工具类
 * <p>使用请依赖 cglib 包</p>
 *
 * @author hubin HCL
 */
public final class BeanUtils {

  private BeanUtils() {
  }

  /**
   * 将对象装换为 map,对象转成 map，key肯定是字符串
   *
   * @param bean 转换对象
   * @return 返回转换后的 map 对象
   */
  @SuppressWarnings("unchecked")
  public static Map<String, Object> beanToMap(Object bean) {
    return null == bean ? null : BeanMap.create(bean);
  }

  /**
   * map 装换为 java bean 对象
   *
   * @param map 转换 MAP
   * @param clazz 对象 Class
   * @return 返回 bean 对象
   */
  public static <T> T mapToBean(Map<String, Object> map, Class<T> clazz) {
    T bean = ClassUtils.newInstance(clazz);
    BeanMap.create(bean).putAll(map);
    return bean;
  }

  /**
   * List&lt;T&gt; 转换为 List&lt;Map&lt;String, Object&gt;&gt;
   *
   * @param beans 转换对象集合
   * @return 返回转换后的 bean 列表
   */
  public static <T> List<Map<String, Object>> beansToMaps(List<T> beans) {
    if (CollectionUtils.isEmpty(beans)) {
      return Collections.emptyList();
    }
    return beans.stream().map(BeanUtils::beanToMap).collect(toList());
  }

  /**
   * List&lt;Map&lt;String, Object&gt;&gt; 转换为 List&lt;T&gt;
   *
   * @param maps 转换 MAP 集合
   * @param clazz 对象 Class
   * @return 返回转换后的 bean 集合
   */
  public static <T> List<T> mapsToBeans(List<Map<String, Object>> maps, Class<T> clazz) {
    if (CollectionUtils.isEmpty(maps)) {
      return Collections.emptyList();
    }
    return maps.stream().map(e -> mapToBean(e, clazz)).collect(toList());
  }

}
